This invention relates to a portable braking device for use with tandemly mounted wheels and more particularly to a portable braking device for use in braking tandem wheels of a wide variety of vehicles.
A convenient method of braking tandem wheels of camping trailers, mobile homes, small or large trucks as well as other vehicles which employ tandemly mounted wheels has long been sought and many attempts at providing a convenient device for accomplishing this have been proposed. The spacing between tandem wheels varies widely which presents certain adjustability problems and many of the prior art braking devices, which have worked in a vertical direction, have used braking elements having a fixed size. The present invention also includes a plurality of parts between two embodiments which can be used interchangeably thereby extending the adjustability of the present invention thereby allowing it to work with a wide variety of wheel spacings.
Early attempts at providing means for braking tandem wheeled vehicles consisted of chock assemblies such as is set forth in U.S. Pat. No. 3,318,419. This device was comprised of two hollow cylindrical members which would be placed on the ground and forceably separated from one another so that they contacted both the ground and the tandem wheels. Another chock type of device is shown in U.S. Pat. No. 3,695,394 wherein two triangular wedge members are also placed on the ground and forced apart until each contacted the wheels similar to the previous device. This device was also lockable in a braking position.
The next phase in the development of braking devices for tandem wheels involved the use of vertically movable upper and lower braking members. The device would be placed in-between the tandem wheels and the upper and lower members would then be moved toward one another so that each member engaged both of the wheels. Devices exemplary of this type are set forth in U.S. Pat. Nos. 3,548,975 and 3,712,424. The devices disclosed in these latter patents employed upper and lower braking members having a fixed size, which limited their use to tandem wheels spaced apart a distance comparable to that fixed size. In addition, both of these latter devices employed braking members which produced only two points of contact with each of the wheels.